The Connecticut River Runs Through It
SCI Helps Assure Regional Future for Canada Lynx, American Marten, and Other Wildlife in the Northeast Kingdom to Northern New Hampshire Linkage
From colonial days forward, the upper Connecticut River has connected people. But with the expansion of roads, settlements and croplands, this narrow lowland—sandwiched between vast conserved forests in Vermont and New Hampshire—has increasingly become a barrier to wildlife.
By the early 20th century, far-ranging, civilization-shy mammals like the Canada lynx and American marten became regionally extinct. Then in the 21st century, large-scale land protection efforts, better wildlife management practices and other factors helped bring those species back.
Now the Staying Connected Initiative (SCI), through its landscape-scale connectivity work, is hoping to assure a place for lynx, marten and other far-ranging mammals in the region for years to come. In 2009, state and nonprofit SCI partners in Vermont and New Hampshire began a successful collaboration to identify, protect, and enhance wildlife corridors in the Northeast Kingdom to Northern New Hampshire (NEK-NNH) linkage.
Modeling Wildlife Pathways
The good news for wildlife is that the NEK-NNH linkage already contains 500,000+ acres of conserved forest where animal movement and dispersal is relatively unrestricted. Those lands include Vermont’s largest boreal forest in the Nulhegan Basin and West Mountain and Victory Basin areas, plus vast tracts of protected forest in New Hampshire’s Connecticut Lakes, Bunnell-Nash Stream forests, the Kilkenney section of the White Mountain National Forest, and the Umbagog National Wildlife Refuge.
The challenge for wildlife is that their travel between these large areas of conserved land is impeded by human activity and development in the Connecticut River Valley and its major tributaries, and in the
Androscoggin River Valley to the east. So SCI set out using computer models to identify the most intact habitat routes by which animals can move between the linkage’s conservation lands—routes referred to as “structural pathways.”
“What we were looking for are the paths of least resistance between the large blocks of conserved forest,” explains Peter Steckler, GIS and Conservation Information Manager with The Nature Conservancy in New Hampshire. “We began by choosing eleven focal species for our model, including American marten, black bear, bobcat, Canada lynx, fisher, long tailed weasel, mink, otter, porcupine, snowshoe hare and wood turtle.”
“If we are going to respond effectively to anticipated habitat fragmentation and climate change, we need to identify the pathways—the corridors—by which wildlife can continue to move through the wider landscape into the future.”
– Peter Steckler, GIS & Conservation Information Mger., NH Nature Conservancy
“Next we identified the types of habitat that each of these focal species is most and least likely to use to move from point A to point B,” Steckler explains. “Of course, a wood turtle or otter, which depend on stream systems, have very different traveling capabilities and habitat needs than a bear or lynx.”
For the purpose of the computer model, each habitat type was assigned a number value. For example, a value of 1 was given to mixed forest, through which most species can move with ease—an area with “high permeability.” A value of 10 went to areas with dense development and roads—areas of “low permeability” that the focal species typically avoid.
Once potential routes for individual species were mapped, an overlay analysis was performed. “We layered individual species corridors atop each other to identify pathways that could accommodate movement for all or most of the focal species,” Steckler says. “The intention was to identify a set of pathways that, if maintained and protected for connectivity, will benefit the movement and dispersal needs of the broader suite of wildlife species in the linkage.” These pathways become the focus of SCI’s conservation planning.
“The Staying Connected model should be applied all over New Hampshire—everywhere. We’ve recognized that we can’t just protect isolated islands of habitat. We need to connect them up for better genetic exchange, and the health of species and ecosystems.
– Will Staats, Regional Wildlife Biologist, NH Fish and Game Dept.
Ground-truthing the Models
Sophisticated wildlife modeling techniques weren’t SCI’s only innovation. “The Staying Connected Initiative’s groundbreaking landscape approach requires close collaboration across political boundaries,” says Carol Foss, Director of Conservation for New Hampshire Audubon. “There we were, people from multiple agencies and conservation groups from two states and two countries, working via conference call, viewing computer models and maps onscreen, sharing knowledge and perspectives, making model adjustments and decisions together. It’s a very efficient way of working, saving time and travel, and reducing our carbon footprint.”
Ten SCI partners are collaborating in the NEK-NNH process, including Vermont and New Hampshire wildlife and transportation agencies, The Nature Conservancy chapters in both states, NH Audubon, the Trust for Public Land, Vermont Land Trust, and The Nature Conservancy of Canada.
The connectivity model was refined further with a roadside tracking survey in 2011-12 along 52 miles of road in the linkage. Another key source of ground-truthing came from experts like Will Staats, Regional Wildlife Biologist at the NH Fish and Game Department. An avid hunter and outdoorsman, he used his local knowledge to fill in corridor details.
“The Connecticut River Valley, while it can be a barrier to wildlife, contains some of the most valuable wildlife habitat in the North Country,” says Staats. “For example, the valley is a great draw for bears, who regularly cross the river for food: corn in the fields, chokecherry in wetlands, and black cherry in hedgerows. Also, areas that are permeable in one season, are not in another—some animals use standing crops as cover, but when those fields are cut, they’re less apt to cross. Each site within the linkage has its own complexity, either conducive or not conducive to wildlife travel.” In 2014, further ground truthing will commence using game cameras to record and confirm wildlife movement.
The focus on connectivity also reflects a shift in regional conservation planning. “We are identifying the most important connecting lands in this linkage rather than just focusing our efforts on protecting large blocks of core habitat,” says Steckler. “That requires us to look at nontraditional conservation properties, such as undeveloped road frontages that can be critical pieces in the puzzle of connecting conservation areas. That’s a different approach and a learning opportunity for us.”
Identifying Key Corridor Sites and Actions to Enhance Connectivity
With modeling complete, the Staying Connected partners prioritized the best wildlife pathways. Then the team selected tools from the SCI connectivity toolbox—including land protection, habitat restoration, and road barrier mitigation—and determined which tools would best apply in which location to protect and enhance landscape permeability.
Land protection has proven especially effective in the Maidstone Bends area—an eight-mile meandering stretch of the Connecticut River with floodplain forest abutting hay fields, oxbow ponds, and emergent marshes. Here The Nature Conservancy’s New Hampshire and Vermont chapters are partnering to conserve significant forested natural areas on either side of the river.
“We were already doing a lot of work at Maidstone Bends to protect and restore the floodplain forests that are critical to the health of the Connecticut River system, so we were delighted to learn that the area is also a key pinch point for wildlife movement east and west across the Valley,” says Phil Huffman, Director of Landscape Conservation and Policy for TNC in Vermont. “The connectivity story has now become a co-equal motivation for our land protection work in the area, and doubles its conservation value.”
SCI has also identified 17 potential sites—old gravel pits, roadsides, fields and riparian areas—where habitat restoration could enhance wildlife corridors. Restoring riparian buffers and reforesting unproductive farmland is already underway at Maidstone Bends. That includes TNC’s planting of disease-tolerant American elms to reestablish this once-dominant floodplain species destroyed by Dutch elm disease.
SCI also identified 23 potential road barrier mitigation sites in the linkage, and made enhancement recommendations. “We did a driving tour of the corridors, getting out and seeing what barriers and crossing areas—habitat, slopes, culverts, bridges, and guardrails—actually look like,” says Foss. “That tells you more than models ever can.” Conservation and transportation experts brainstormed on the spot to determine the best connectivity enhancement strategies for each site—ranging from wildlife signage and reduced speed limits, to roadside re-vegetation and other techniques.
“Lynx and marten just recently re-colonized Vermont, and they found their way here via forest pathways. That’s why understanding the regional connectivity puzzle has now become such a high priority for state wildlife agencies and conservation groups.”
– Phil Huffman, Director of Landscape Conservation and Policy, Vermont TNC
“The hope is that when a stretch of road within a major identified corridor comes up for rehabilitation or reconstruction, we’ll be able to economically redesign it, enlarging a culvert for example, to make it more wildlife-friendly,” says Catherine Goodmen, Senior Environmental Manager for the NH Department of Transportation. “I think the SCI collaboration will be very fruitful for long range transportation planning.”
Adding connectivity into the town and regional planning mix is also key. “So much planning happens at the municipal scale, but when it comes to wildlife, we need to think bigger, because what one town does can impact what happens in the communities around it,” explains Emily Preston, Wildlife Biologist at the NH Fish and Game Department. “Staying Connected provides planning data that towns can really use.”
“It’s the connectivity of the whole system—linking large forest blocks between New York, Vermont, New Hampshire and Maine, between the U.S. and Canada—that will enable animals like lynx and marten to persist in the Northern Forest,” says John Austin, Land and Habitat Program Director for the VT Fish and Wildlife Department. “These are important native species that contribute to ecosystem health and resilience.”
“Their return to places like the Northeast Kingdom is something to celebrate,” Austin says. “It demonstrates the effectiveness of our conservation investments—it’s one of the great dividends we get for the dollars spent over the years to conserve and manage land. Staying Connected helps protect that investment for the future.”